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Overall D. melanogaster Cohort Viability as A Pollution Indicator of the Atmospheric Air of Urban Landscapes
2020
Rudenko, S. S. | Leheta, U. V. | Rudenko, V. P. | Kostyshyn, S. S. | Bialyk, V. D.
The method of air pollution level evaluation of urban landscapes on the basis of D. melanogaster cohort analysis has been suggested. The method implies the binding to the landscape areas of the city. Within each landscape area traps and cultivators for D. melanogaster have been installed in sanitary-protective zones of various enterprises as well as on the background territory with the least level of anthropogenic load serving as the control. Based on specifically elaborated technique for field conditions, the amount of eggs, third instar larvae, pupae and imago has been calculated. Then, using the computer program ImageJ, the square under the curves of cohort survival has been determined which is considered overall cohort viability (OCVD.m). The previously mentioned indicator considers cohort survival at all stages of ontogenesis. In addition, the expressed in percentage indicator of oppression (IO OCVD.m) in relevance to the control OCVD. m affects the level of air pollution of urban landscapes by emissions of various enterprises. The relevance between these indicators is determined by a four-level scale elaborated specifically for the purpose. The method has been tested based on technogenic landscapes of Chernivtsi, Ukraine. The sensitivity of the suggested indicator for a wide range of pollutants has been proved and its ability to respond to different levels of greening of similar enterprises has been shown.
Afficher plus [+] Moins [-]Dust Crises and its Regional Geopolitical and Security Impact in West Asia
2020
Abdi, A. | Yazdanpanah, Q. | Javadi, Z.
Western Asia has recently become an arena for significant upheavals of various kinds, be it political, safety-related, geopolitical, social, etc. These have in turn focalized the salience of the region as well as its ensuing situation and challenges on a global perspective. Such a naturally-born phenomenon is characterized, amidst other factors, by its transregional quality, granting it some sort of geopolitical peculiarity. The occurrence of haze would implicate a merged endeavor on part of the countries, engaged in this cross-regional abnormality. This joint endeavor is, however, hindered and at times exacerbated due to certain political inconsistencies among the countries, undoubtedly rising from differences in ideology, religion, politics, and social standards. In this light, the present study seeks to inquire the impacts of haze, as a geopolitical phenomenon, on involved countries. It also tries to find out whether subsequent implications of this predicament could in effect be employed to establish new relations among rather-standoffish nations or if they are merely components of a cold relation among countries and could intensify each nation’s problems, reducing the overall quality of life further. The findings indicate that despite the existent domestic and transregional problems, public opinion tends to establish joint cooperation among the engaged countries. This is not in the least a result of fear of a low life quality among the inhabitants of the said nations.
Afficher plus [+] Moins [-]Diversity of Lichen Flora in Mt. Kitanglad Range Natural Park, Kaatuan, Lantapan, Bukidnon
2020
Cababan, M.L. | Memoracion, M. M. | Naive, M. A.
This study was conducted to identify and classify the lichens; determine the diversity index and richness of lichens. A total of 36 species belonging to six genera under three families was identified. Lichen species were mostly found at moderate high altitudinal range with an elevation of 1,131 meters above sea level and open areas where they received adequate sunlight with high moisture and humidity contents. Diversity, composition and altitudinal distribution of lichens was evaluated in Mt. Kitanglad Range, Kaatauan, Lantapan, Bukidnon, Philippines a wet forest type forest. The maximum species richness was reported on Usnea rubicunda Stirt. The abiotic factors were shown to be essential in adapting the relative abundance of lichens for it is capable to survive in the range of light levels, it appears that drier and lighter conditions competitively favored. Additionally, lichen diversity is dependent on the climatic and environmental conditions which makes them as an excellent biological indicators of ecosystem changes in the forests of Mindanao Island, Philippines.
Afficher plus [+] Moins [-]Response surface method Optimization of the Dyes Degradation using Zero-Valent Iron based Bimetallic Nanoparticle on the Bentonite Clay Surface
2020
Sabouri, M. R. | Sohrabi, M. R. | Zeraatkar Moghaddam, A.
Immobilizing of zero-valent iron in mono- and bi-metallic systems on the bentonite clay surface as new nanocatalyst were synthesized and used to degrade model acidic dyes from aqueous media. The Fourier-transform infrared spectroscopy, scanning electron microscopy-energy dispersive X-ray spectroscopy, transmission electron microscopy, X-ray diffraction, and Brunauer-Emmett-Teller analysis were used to characterize the synthesized nanocomposites, which demonstrated successful loading of nanoscale Fe-Cu bi-metallic onto bentonite support. Different variables controlling the congo red, methyl orange and methyl red dyes degradation using zero-valent iron based bimetallic nanoparticle on the bentonite clay surface as new nanocatalyst were concurrently optimized through an experimental design. Basic evaluations proved the nanocatalyst quantity, medium pH, initial dye concentration, and contact time as the most important variables influencing the degradation phenomenon and hence a response surface methodology based on the central composite design was conducted to determine the relations between the variables and the degradation efficiencies. The statistical factors (e.g. R2 and F-value) of the derived models were considered. Using response surface plots obtained through the models, the effects of the variables on the degradation efficiencies for each dye were assessed. Also, the Nelder-Mead non-linear optimizations were performed and the optimal degradation efficiencies at a 95% confidence level were determined which were found to comply with the respective experimental response values.
Afficher plus [+] Moins [-]Assessment of Accumulation and Potential Health Risk of Cr, Mn, Fe, Cu, and Zn in Fish from North-Eastern Mediterranean Sea
2020
Can, M. F. | Yılmaz, A. B. | Yanar, A. | Kılıç, E.
Heavy metal accumulation in aquatic organisms has been an important issue due to environmental pollution resulting from anthropogenic activities. In this study, Cr, Mn, Fe, Cu, and Zn in the selected fish species (Mullus barbatus, Solea solea, and Siganus rivulatus) from three consecutive bays (İskenderun, Mersin, and Antalya from North-Eastern Mediterranean Sea) were considered to provide some information on heavy metal accumulation level and assessment of their health risk on both general and fishermen populations. There were some significant differences inter- and intra- species/ tissues/bays. The stability in heavy metal accumulation in fish tissues varied and the most stable tissue for Cr, Cu, Fe, Mn and Zn were determined as skin, muscle, liver, liver and, muscle, respectively. In general, the lowest heavy metal values were observed in the fish muscle. The Target Hazard Quotients (THQ) and Total Target Hazard Quotients (TTHQ) values based on muscle were not exceeded 1.00. Therefore, these results suggest that both general and fishermen populations are not subjected to the significant potential health risk from those bays.
Afficher plus [+] Moins [-]Effect of Composting Process on Some Chemical-Biological Properties and Heavy Metals Behavior of Municipal Sewage Sludge as Affected by Various Bulking Agents
2020
Saffari, M. | Saffari, V. R. | Khabazzadeh, H. | Naghavi, H.
The present study tries to investigate the effect of composting process on some properties and heavy metals status of two municipal sewage sludge (MSS) as affected by three different organic bulking agents (BAs) at three levels (10%, 25%, and 45% V/V). According to the results, the composting process could reduce the fecal coliform to class A, a reduction more obvious in treatments with BAs than produced composts without them. Changes in the chemical properties of the composts vary according to the type of MSS and Bas. Based on the compost quality standard, most of the produced samples are classified in compost-class II. Examination of the total form of three heavy metals (HMs: Zn, Ni, Fe) of both MSS shows that composting process without BAs increases the HMs total concentration, but using of BAs have not been clear trends. In the contrary, BAs application reduced the available form of Fe and Ni, but increased the Zn available form. Examination of chemical forms of each studied HMs also shows that the composting process reduces the Ni and Fe mobility factor, but increases that of Zn. Generally, while, prepared composts can classify into the compost-class II, based on their properties, the high concentration of total Zn above the standard limit makes it extremely restrictive to be used as class II compost. However, according to EPA regulations, the composts with this concentration of Zn can be used as a relatively safe organic material on agricultural land.
Afficher plus [+] Moins [-]Bio-Accumulation of Lead and Cadmium by Radish (Raphanus sativus) and Cress (Lepidium sativum) under Hydroponic Growing Medium
2020
Hedayatzadeh, F. | Banaee, M. | Shayesteh, K.
In order to investigate the accumulation and bio-absorption of lead and cadmium in radish and cress, the present study has been conducted in a completely randomized design in three replicates in a hydroponic growing medium. The first factor includes the plant type at two levels (radish and cress), and the second factor is consisted of lead (Pb) (first experiment) at two levels (50 and 100 mg/L), cadmium (Cd) (second experiment) at one level (10 mg/L), and a combination of lead and cadmium (third experiment) again at two levels. After 23 days, roots and aerial parts of both plants have been dried for 48 hours at 70°C in an oven. Then, half gram (0.5 g) of the dried templates has been used to measure the accumulation of Pb and Cd by means of an atomic absorption spectrometer. The highest amount of Pb in radish and crest roots belong to 100 mg/L concentration and the combined Cd (10) + Pb (100) mg/L treatment, respectively, and the highest amount of Cd occurs in Cd (10) + Pb (50) for radish roots and in Cd (10) + Pb (100) combination for cress. Moreover, the Translocation Factor (TF), with a value below 1 and higher bio-concentration factor (BCF) in roots, compared to the aerial part of both radish and cress, seem to be due to the low capability of these plants to transfer Pb and Cd from roots to aerial part. There is a high potentiality for lead accumulation in the roots that prevent its transfer to the aerial part.
Afficher plus [+] Moins [-]Effect of Barley and Oat Plants on Phytoremediation of Petroleum Polluted Soils
2020
Barati, M. | Safarzadeh, S. | Mowla, D. | Bakhtiari, F.
Total Petroleum Hydrocarbons (TPHs) are one of the most dangerousorganic contaminants in the environment. Therefore, the remediation of the oilcontaminatedsoil is necessary. The growth of barley and oat plant was studied in thecontaminated soils (4, 6, 8% TPHs) during 5 months. Plant height, wet and dry weight ofshoots and roots of both plants were measured. Results showed that oat and barley height,wet and dry weight of shoots and roots decreased with increasing contamination levels.Regardless of the plants species, the highest rate of TPH reduction was observed in soilwith 4% contamination and decreased with increasing the contamination level. The TPHsconcentration in the rhizosphere of barley and oat decreased by 29.66 and 24.04% at the6% TPHs level and by 21.24 and 17.48% at the 8% TPHs level, respectively. Cultivationof barley and oat plants significantly accelerated the biodegradation of hydrocarbons andreduced TPHs content in soil as compared to unplanted soil.
Afficher plus [+] Moins [-]Algal Indices as a Biomonitoring Tool to Assess Eutrophication in the Urban Ponds: a Case Study
2020
Vishal, R. | Meeta, B.
Eutrophication of the urban water bodies is one the biggest challenge causing severe ecological and economic loss. Urban ponds are more prone to eutrophication due to their small size and polluted catchment areas. Biomonitoring using phytoplankton provides cost-effective estimation of the level of eutrophication. Ten urban ponds in different areas of the Mumbai city were chosen to investigate the phytoplankton community structure, and level of eutrophication. We assessed the 3 algal indices viz. Shannon-Wiener indices, Palmer and Nygard's (Myxophycean and diatom) indices. Linear relationship of these indices was tested against Carlson trophic state indices in order to assess the effectiveness of these indices to measure the degree of eutrophication in urban lakes. All ten lakes were found to be eutrophic, of which two were very low eutrophic (TSI – 53.74-53.95), four were low-mid eutrophic (TSI – 55.18 – 57.5), and four lakes were mid eutrophic (TSI 61.4 – 62.2). Shannon-Wiener indices (r= -0.73) and Myxophycean indices (r= 0.77) showed strong correlation with TSI whereas Diatom indices (r= -0.12) and Palmer’s Algal Pollution Indices (r= - 0.47) showed weak correlation with TSI. Thus study found that Shannon-Wiener indices and Myxophycean indices are reliable and cost effective means to assess the eutrophication of urban ponds in Mumbai.
Afficher plus [+] Moins [-]Physiological and Growth Responses to Pollutant-Induced Biochemical Changes in Plants: A Review
2020
Mulenga, C. | Clarke, C. | Meincken, M.
Industrial activities compromise the ambient air quality at a local, regional and global level through gaseous and dust emissions. This study reviews uptake mechanisms and the associated phytotoxicity of pollutants in plants, focusing on heavy metals and SO2. It further describes detoxification mechanisms and the resultant biochemical and physiological changes in plants. Finally, the morpho-physiological and growth responses to stress-induced biochemical changes are discussed. Heavy metals and SO2 enter the plant tissue through the stomata, cuticular layers, lenticels and root hairs. In the plant cells, SO2 converts to SO32- or SO42- ions upon reacting with water molecules, which in excess are toxic to plants. However, the detoxification process of SO32- increases the production of reactive oxygen species (ROS). ROS are toxic to plants and damages biomolecules such as lipids, proteins, carbohydrates and DNA. On the other hand, heavy metals, such as Cu and Fe catalyse the Fenton/Haber-Weiss reactions, breaking down H2O2 into OH•. Additionally, Pb and Zn inhibit the activities of ROS-detoxifying enzymes, while other heavy metals bind to cellular layers making them rigid, thereby reducing cell division. Therefore, pollutant toxicity in plants affects biochemical parameters damaging organic molecules and limiting cambial activity. Damaged biomolecules inhibit the plant's capacity to carry out physiological functions, such as photosynthesis, stomatal functions, transpiration and respiration while impaired cambial activity reduces cell division and elongation resulting in reduced plant growth and productivity.
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